Handle utf8 character as a fill character in alignment

[dsvi]

If you use unicode symbols as fill character for alignment, you get runtime error
for example, for:
print(u8" {:─<5}─{}\n", i, str);
there supposed to be outputs like this

 0─────2019 March 27 06:32:41                                                                                                                                                 
 1─────2019 March 27 14:43:20                                                                                                                                                 

but there is runtime error:
missing '}' in format string

[vitaut]

Thanks for reporting. This is a known limitation: only single code units can be used in the fill field at the moment.

[vitaut]

format_specs can accommodate multibyte specs as of e4f84ee, but need to hook this to the parsing and formatting logic.

[vitaut]

{fmt} now supports UTF-8 code points as fill. For example

#include <fmt/core.h>

int main() {
  fmt::print(" {:─<5}─{}\n", 0, "2019 March 27 06:32:41");
}

prints

 0─────2019 March 27 06:32:41

as expected.

[gocarlos]

should this work out of the box?

this code:

  fmt::print(
                  "┌{0:─^{2}}┐\n"
                  "│{1: ^{2}}│\n"
                  "└{0:─^{2}}┘\n", "", "my great message.", 72);
  fmt::print(" {:─<5}─{}\n", 0, "2019 March 27 06:32:41");

creates this on windows

[vitaut]

You should compile with /utf-8, otherwise MSVC will corrupt your string literals.